Method and apparatus for recording and reproducing picture information and timely reproducing images by graphic codes

ABSTRACT

Method of recording and reproducing picture information and a recording medium on which the picture information is recorded by the method, and an apparatus for playing such a recording medium. In addition to video format signal and a coded information signal, graphic codes including picture information are recorded on the recording medium correspondingly to playback sections of the video format signal, the graphic codes being inserted as the subcode of the coded information signal. At the time of playback of the recording medium, a video signal according to the graphic codes corresponding to the playback section of the video format signal is generated each time one playback section of the video format signal is played back. Preferably, presence or absence of the graphic codes is displayed each time one playback section of the video format signal is played back.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to method and apparatus of recording andreproducing picture information on and from a recording medium such as adigital audio disc, and so on, and relates to a recording medium.

2. Description of Background Information

A system is proposed in which picture information is recorded andreproduced in the form of a subcode on and from a digital audio dischaving a diameter of 12 cm, generally called compact disc (abbreviatedas CD hereinafter). The subcode is made up of eight subcode bits, andbit groups forming the subcode are divided into eight channels denotedrespectively by letters P, Q, R, S, T, U, V, and W. In the method inwhich the picture information is recorded and reproduced in the form ofthe subcode, data corresponding to picture information is configuredsuch that a symbol is formed by 6 bits of channels R through W out ofthe 8 bits forming the subcode, and 98 symbols are treated as one block,as illustrated in FIG. 1. Two symbols in the 98 symbols are used as async signal, and 24 symbols obtained by dividing the remaining 96symbols, by four are treated as a minimum unit of data, i.e. a "pack",which constitutes one instruction of picture processing.

More specifically, the first symbol (referred to as symbol 0hereinafter) of the 24 symbols shows one of several modes. A symbol 1following this symbol 0 forms instruction which indicates the sort ofthe instruction. Symbols 2 and 3 following the symbol 1 constitute aparity Q which is an error correction code. Symbols 4 through 19following the parity Q constitute a data field, and include informationsuch as color information. Finally, symbols 20 through 23 following thedata field constitute a parity P which is an error correction code forprotecting the information in the "pack".

On the other hand, there are four modes, i.e. "zero mode","line-graphics mode", "TV-graphics mode", and "user's mode". The "zeromode" is provided for a case where no operation is required for pictureson the display screen, that is, the original image is to be maintained,and all data in the "pack" are 0 for this mode.

The "line-graphics mode" is provided for such a case that a liquidcrystal display is provided on the front face of the player, to displaynotes such as an explanation of a music selection. As shown in FIG. 2, apicture area being long sideways is formed by pixels which are arrangedin 288 columns and 24 rows. In other words, each row includes 288 pixelsand each column includes 24 pixels. The term "pixel" means the minimumdisplay element of a picture, and it is general that the pictureprocessing is performed by using picture composing units designated as"fonts" each of which is made up of pixels divided into 6 columns and 12rows.

The number of "fonts" which can be displayed in the "line-graphics mode"is 48 in the lateral direction, and in the column direction, and thisarea is designated as "screen area". For providing the scroll function,a line of "fonts" is added to the upper and lower outer peripheries andthe right and left peripheries of the Screen area, to form a picturearea having 50 "fonts" in the direction of row, and 4 "fonts" in thedirection of column. The subcode is formed so that the pictureprocessing is performed by using a memory having addresses eachcorresponding to each pixel in this picture area. In addition, the areaoutside the "screen area" is designated as "border".

The "TV-graphics mode" is a mode for displaying images on the TV screen,and a picture is formed by pixels arranged in 192 rows and 288 columnsas illustrated in FIG. 3. The number of "fonts" which can be displayedin the "TV-graphics mode" is 48 in the direction of row, and 16 in thedirection of column. Also in this "TV-graphics mode", the subcode isformed so that the picture processing is performed by using a memoryhaving addresses each of which corresponds to each pixel in a picturearea having 50 "fonts" in the direction of row, and 18 "fonts" in thedirection of column, made by adding a line of "fonts" to the upper andlower peripheries as well as the right and left outer peripheries of the"screen area".

As instructions for the picture processing, there is an instruction forpainting out the whole picture area by one certain color, an instructionfor drawing a picture in one "font" on the screen by using two differentcolors, an instruction for moving the whole picture upward, downward orsideways, and so on.

Additionally, in the 8-bit groups forming the subcode, the Q bitsforming the channel Q include time information corresponding to thetrack length to a certain position of each information data which isrecorded from the beginning of the program area of CD, and form addresstime data which can be used as positional data representing therecording position. On the other hand, the P bits forming the channel Pform data including information relating to a pause between two musicselections.

In the above-described system of recording and reproducing pictureinformation as the subcode, as many as 16 picture channels can bedesignated at the most. Specifically, a "write fontforeground/back-ground" instruction is used in the "TV-graphics mode",which has such a structure as illustrated in FIG. 4. This is aninstruction for writing font data of the symbols 8 through 19 inpositions having a row address defined by the symbol 6 and a columnaddress defined by the symbol 7. For the pixels whose font data is "0",a color of a color number determined by the "color 0" is designated as abackground color. For the pixels whose font data is "1", a color of acolor number defined by "color 1" is designated as a foreground color.At the same time, subpicture channels can be designated by using fourbits of the channels R and S of the symbols 4 and 5. By this feature, asmany as sixteen picture channels can be designated. Sixteen sorts ofpictures are previously recorded on a disc for example, and on theplaying side, a desired picture channel can be selected at the time ofplaying by this scheme of designating the picture channel.

In addition, the sixteen colors indicated by the color number "0"through "5" are set by a "load CLUT color 0 through color 15 (load colorlook-up table color 0 through color 15)" instruction. The "load CLUTcolor 0 through color 15" instruction is an instruction having astructure illustrated in FIG. 5, and setting the contents of a colorlook-up table showing the color of pre-set color numbers orforeground/background color numbers. It is necessary to designatesixteen colors in total. However, since four bits are used respectivelyfor each of RGB to indicate a color, two symbols are required forsetting one color. Therefore, eight colors are set by one "pack " atmost. With this circumstances, this instruction is divided into twoinstructions respectively designating eight colors of the first half,and eight colors of the second half.

The instruction code for the colors of the first half, i.e. the color 0through the color 7, is determined to be "30", and the instruction codefor the colors of the second half, i.e. the color 8 through color 15 aredetermined to be "31". The mixing of colors for each of the color numberis as follows. Red color is represented by four bits of the channels Rthrough U of even symbols allotted to the color number. Green color isrepresented by four bits, i.e. two bits of the channels V and Wfollowing the channels R through U of the even symbols, and two bits ofthe channels R and S of odd symbols. Blue color is represented by fourbits of channels T through W following the channels R and S of the oddsymbols. Therefore, 2⁴ (=16) sorts of gray scales are available for eachcolor, and preparation of 16³ (=4096) colors are possible since threecolors (RGB) are used. In addition, a gray scale "0000" corresponds tothe darkest state, and a gray scale "1111" corresponds to the brighteststate.

On the other hand, a system has been invented by the applicants of thepresent application and others and a patent application has been filedfor that invention, in which an FM modulated video format signal isrecorded on a recording medium together with a digital audio signal withgraphic codes including picture information being inserted thereto,using the above-described system of recording and reproducing pictureinformation as the subcode, and which is arranged so that, at the timeof the playback of the recording medium, pictures produced from thesubcode can be inserted to the pictures produced from the video formatsignal. However, it has been discovered that if playback is startedafter a search operation is commenced for searching a desired playbacksection of the video format signal (such as a chapter), a problem arisesthat the reading of graphic codes recorded at a position correspondingto the beginning of a chapter becomes incomplete, and a part of a seriesof picture processing instructions is not read-out so that a incompletepicture is displayed.

OBJECT AND SUMMARY OF THE INVENTION

The present invention is based the recognition of the above mentionedproblem, and an object of the present invention is to provide a pictureinformation recording and reproducing system in which, at the time ofthe playback of the recording medium on which, in addition to a videoformat signal and a coded information signal, graphic codes includingpicture information are recorded as being inserted as the subcode of thecoded information signal, pictures produced from the subcode can bedisplayed in a precise manner even if the playback operation is startedafter a search operation is issued for searching a particular playbacksection of the video format signal.

In order to attain the above object, a picture information recording andreproducing system according to the present invention is characterizedin that, in addition to a video format signal and a coded informationsignal, graphic codes including picture information are recorded on arecording medium corresponding to playback sections of the video formatsignal, the graphic codes being inserted as the subcode of the codedinformation signal, and during playback of the recording medium,generating a picture signal according to the graphic codes duringplayback of each section.

According to another aspect of the invention, at the time of theplayback of the recording medium, the presence or absence of the graphiccodes is displayed each time of the playback of one playback section.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the recording format of subcode data;

FIG. 2 is a diagram showing the structure of picture in the"line-graphics mode";

FIG. 3 is a diagram showing the structure of picture in the "TV-graphicsmode";

FIG. 4 is a diagram showing the construction of "write fontforeground/background" instruction;

FIG. 5 is a diagram showing "load color look-up table color 0 throughcolor 7" instruction;

FIG. 6 is a block diagram showing the construction of a recordingapparatus according to the present invention;

FIG. 7 is a diagram showing the sort of recording modes;

FIG. 8 is a diagram showing the construction of "load transparencycontrol table";

FIG. 9 is a diagram showing the correspondency between the bit patternof TCB and the mixing ratio;

FIG. 10 is a diagram showing recording area of a composite disc;

FIGS. 11A through 11C, when combined, are a block diagram showing anapparatus for reproducing picture information recorded on a disc inaccordance with recording and playback method according to the presentinvention;

FIG. 11 is a diagram showing the arrangement of FIGS. 11A through 11C;

FIG. 12 is a block diagram showing a specific configuration of videoformat signal processing circuit 30 in the apparatus shown in FIGS. 11Athrough 11C;

FIGS. 13 and 14 are flowcharts showing the operation of processor insystem controller 32 of the apparatus shown in FIGS. 11A through 11C;and

FIGS. 15 and 16A through 16C are diagrams showing pictures obtained bythe apparatus shown in FIGS. 11A through 11C.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An embodiment of the method according to the present invention will beexplained with reference to FIGS. 6 through 16C of the accompanyingdrawings.

In FIG. 6, two-channel audio signals and a video format signal,outputted from a video tape recorder for example, are respectivelysupplied to input terminals IN₁, IN₂, and IN₃. The video format signalis supplied to an FM modulator 1 and a chapter number separating circuit(code separating circuit) 2. In the FM modulator 1, a carrier signal ofa predetermined frequency is FM-modulated by the video format signal. AnFM signal outputted by this FM modulator 1 is supplied to a multiplexingcircuit 3. The chapter number separating circuit 2 is configured toseparate codes indicating the chapter number from control codes, such asthe Phillips codes, inserted in predetermined sections of the videoformat signal.

On the other hand, left and right-channel audio signals are supplied toan analog-to-digital converting circuit 4 The analog-to-digitalconverting circuit 4 is configured to perform the sampling of each ofthe left and right-channel audio signals at a sampling frequency of 44.1kHz for example, to generate two digital data signals corresponding totwo sampled values obtained by the sampling, and to output the digitaldata signals after processed by time division multiplexing. The outputdata of this A/D converter 4 is supplied to a CD system encoder 6through an error correction code adding circuit 5 which interleaves thedata, the error detection, and the addition of codes for the errorcorrection. To the CD system encoder 6, an output signal of the controlsignal generating circuit 7 and an output signal of the error detectionand correction code adding circuit 8 are supplied. The control signalgenerating circuit 7 is configured to generate data such as dataindicating the time elapsed after the start of the supply of audiosignals to the input terminals IN₂ and IN₃, and data indicating a pausebetween music selections or a portion within one music selection of theaudio signals.

On the other hand, output data of the graphic code generation device 9is supplied to the error correction and correction code adding circuit8. The graphic code generation device 9 is configured to record aplurality of codes corresponding to a plurality of picture processinginstruction groups respectively corresponding to each chapter of thevideo format signal, which are previously inputted by key operations forexample, and to read-out codes corresponding to a picture processinginstruction group corresponding to a chapter indicated by a chapternumber data output from the chapter number separating circuit 2. Theerror detection and correction code adding circuit 8 is configured tointerleave and error detection of the output data of the graphic codegeneration device 9 and the addition of the correction code.

The CD system encoder 6 is configured to form a recording signal bymaking the output of the control signal generation circuit 7 data of thechannels Q and P, and making the output of the graphic code generatingdevice 9 through the error detection and correction code adding circuit8 data of the channels R through W, and inserting that data into thedigital data from the A/D converter 4. Output signal of this CD systemencoder 6 is supplied to a modulator 10 and converted to an EFM (Eightto Fourteen Modulation) modulation signal. The output signal of thismodulator 10 is supplied to the multiplexing circuit 3, and processed bya frequency multiplexing with the FM-modulated video format signal.

The output signal of the multiplexing circuit 3 is supplied to anoptical disc recorder of known arrangement (not shown) in which thestrength of a light beam irradiated on the recording surface of a discrotated at a constant linear velocity for example, is modulated by thissignal. As a result, the graphic codes including picture informationcorresponding to chapters of the video format signal are recorded on therecording disc as the subcode of the digital audio signal, in additionto the video format signal and the digital audio signal as the codedinformation signal.

The graphic code generating device 9 is configured to generate codescorresponding to picture information processing instructions in theconventional system of recording and reproducing picture informationusing the subcode, and also codes corresponding to picture informationprocessing instructions in a system of recording and reproducing pictureinformation using the subcode, which is invented by the applicants ofthe present application and others, and for which a patent applicationhas been already filed.

In the above-mentioned system of the prior application, for enabling thedisplay of the picture produced from the video format signal and thepicture produced from the subcode at the same time in a single picture,a code to be inserted as the symbol 0 is set in order to designate anadditional mode, that is, "graphic mode with motion picture" as shown inFIG. 7, in addition to the "zero mode" the "line-graphics mode", the"TV-graphics mode" and the "user's mode" which are also used in theconventional system.

The structure of pictures in the "graphics mode with motion picture" isidentical with that in the "TV-graphics mode", and an instructiondesignated as "load transparency control table" is provided. This "loadtransparency control table" instruction is an instruction fordesignating the mode for each pixel in picture area. Three modes aredesignated by this instruction, and those are namely, "transparentmode", "mixing mode", and "nontransparent mode". In these three modes,different values are selected for the mixing ratio between a videoformat signal obtained by the subcode and a video format signal which isrecorded by multiplexing together with the coded information signalincluding the subcode.

The bits in the channels R through W of each of the symbols 4 through 8and the channels R and S of the symbol 9 constitute a series of codesTCB-0 through TCB 15 which respectively designate one of modes whichwill be described later for each of the group of pixels to which one ofcolors, which are registered as color number "0" through color number"15", is allotted. FIG. 9 shows a relationship between bit patterns ofthe codes TCB-0 through TCB-15 and the modes designating the mixingratio, and the mixing ratio in each mode.

By the recording system shown in FIG. 6, a composite disc 20 asillustrated in FIG. 10 can be produced. As shown, the composite disc 20has a first area 20a disposed in an inner peripheral area of the disc(this area being referred to hereinafter as the CD area) in which isrecorded a digital audio signal with the subcode including pictureinformation being inserted, and a second recording area 20b (this areabeing referred to hereinafter as the video area) containing anFM-modulated video format signal and a superimposed digital audio signalwith the subcode including picture information being inserted, whereinthe superimposition is performed by using a frequency multiplexingsystem. Since the video format signal contains higher frequencycomponents than the PCM signal, it is necessary to rotate the disc at ahigher speed of rotation during the recording of signals in the videoarea 20b, than during the recording of the signal in the CD area 20a.Therefore of course it is necessary, in the playing time, to reproducethe signal by rotating the disc at the higher speed during the playbackof video area 20b, than during the playback of CD area 20a. The speed ofdisc rotation during the playback of CD area 20a is several hundredr.p.m., whereas during the video area playback the speed of rotation istwo thousand plus several hundred r.p.m. for playback from the innermostperiphery of that area, and is one thousand plus several hundred r.p.m.for playback from the outermost periphery of that area, so that thespeed of rotation is extremely high during video area playback.

In the head portions of the CD area 20a and the video area 20b, thererespectively are provided a lead-in area in which are recorded, as thesubcode, index codes relating to the contents recorded in each area,such as first and second code groups corresponding to each area by therepetition of index codes which respectively indicate start and endtimes of small portions which together constitute each area. Inaddition, the index codes of the audio lead-in area include informationshowing whether the disc itself is a composite disc or a disc of anothertype.

FIGS. 11A through 11C show a disc player capable of playing thecomposite disc. As illustrated in these figures, a disc 20 is rotated bya spindle motor 21, and information recorded thereon is read-out bymeans of a pickup 22. The pickup 22 incorporates therein an opticalsystem including a laser diode, an objective lens, and photo detectors,a focus actuator for driving the objective lens in a direction of itsoptical axis with respect to the information recording surface of thedisc 20, a tracking actuator for biasing the beam spot (informationdetecting point) issued from the pickup 22 with respect to the recordingtracks in a direction of disc radius, and so on. The pickup 22 ismounted on a slider 23 which is linearly movable in the direction ofdisc radius by the drive of a transmission mechanism 25 which in turnhas a slider motor 24 as a source of driving force, and made by acombination of rack and pinion gears. A read-out RF (radio frequency)signal output by the pickup 22 is supplied to a video format signaldemodulating and processing circuit 30 and a coded informationdemodulating and processing circuit 31 through an RF amplifier 26.

The video format signal demodulating and processing circuit 30 includesa demodulation circuit which for example demodulates the RF signal andconverts it to a video format signal and a memory which stores the videoformat signal after digitizing it, and configured to selectively outputone of the video format signals output by the demodulation circuit andthe video format signal read-out from the memory in accordance with achangeover command from a system controller 32. The video format signaloutputted by the video format signal demodulating and processing circuit30 is supplied to a video switch 33. In addition, the video formatsignal demodulating and processing circuit 30 is further provided with aseparating circuit which separately extracts a horizontal sync signal h,a vertical sync signal v, and control data c from the demodulated videoformat signal, and the separated horizontal and vertical sync signals hand v, and the control data c are supplied to each part such as thesystem controller 32.

On the other hand, the coded information demodulating and processingcircuit 31 is provided with a selector switch 35 which changes itsswitch position in accordance with the area to be played (the CD area orthe video area) during the playing of a composite disc. The selectorswitch 35 is operated to a position a during the playing of the CD area,and to a position b during the playing of the video area, and thechangeover is performed in response to a changeover command issued fromthe system controller 32. In the case of the composite disc, the speedof disc rotation changes extremely between the CD area and the videoarea, and the PCM audio signal is for example an EFM (Eight to FourteenModulation) signal. For the video area, the EFM signal will adverselyaffect on the low frequency component of the video signal treated by theFM modulation process if the digital signal is directly superimposed onthe FM video signal at the time of recording. Therefore, the digitalsignal, i.e. the EFM signal is recorded at a level which is lower thanthe video carrier level by several tens of dB, although the degree ofmodulation is almost the same for the EFM and video signals. Thus thefrequency characteristic and amplitude of a playback EFM signal willboth be different, for the cases of CD area playback and video areaplayback respectively. However, a common demodulating system is used forthe CD area playback and the video area playback. This is made possibleby switching signal processing systems for the playback EFM signals ofthe CD area and the video area respectively.

Specifically, during playback of the CD area, the playback RF signal isan EFM signal, which is subjected to frequency characteristiccompensation by an equalizer circuit 36 having a predeterminedequalizing characteristic, and is amplified at a predeterminedamplification factor by an amplifier 37. During the playing of the videoarea, on the other hand, the playback RF signal is an FM video signalwhich is combined with an EFM signal. The EFM signal is extracted by anEFM signal extracting circuit 38 which is made up of an LPF and so on,then is subjected to frequency characteristic compensation by anequalizer circuit 39, which has a different equalization characteristicfrom the equalizer circuit 36, to be then amplified by an amplifier 40,which has a higher gain than that of the amplifier 37. In this way, anEFM signal is derived whose frequency characteristic and amplitude arealmost the same as the EFM signal obtained during CD area playback.

During playback of a CD disc, the selector switch 35 is held in positiona.

The playback EFM signal selected by the selector switch 35 is suppliedto an EFM demodulation circuit 42 which performs the demodulationprocess, to obtain a PCM data that is digital data including audioinformation of left and right channels which is for exampletime-division multiplexed, and the subcode. The digital data includingaudio information output by this EFM demodulation circuit 42 is suppliedto a de-interleave and interpolating circuit 43. The de-interleave andinterpolating circuit 43 is configured to change back, in cooperativewith the RAM 44, the order of the digital data which was rearranged bythe interleave operation during the recording, in turn send it to anerror correction circuit 45, and to effect the interpolation oferroneous data in the output data of the error correction circuit 45 bythe average value interpolation method for example, when a correctioninability signal is outputted. The error correction circuit 45 isconfigured to perform the error correction operation by using the CIRC(Cross Interleave Reed Solomon Code), and supply the digital data to thede-interleave and interpolating circuit 43, or supply the digital datato the de-interleave and interpolating circuit 43 together with thecorrection inability signal when the error correction is not possible.

The output data of the de-interleave and interpolating circuit 43 issupplied to a D/A (Digital to Analog) converting circuit 46. The D/Aconverting circuit 46 includes a de-multiplexer which separates fromeach other the digital data of left and right-channel audio informationcombined by the time division multiplexing, and left and right-channelaudio signals are reproduced. After their unnecessary components areremoved at LPFs (Low Pass Filters) 47 and 48, the reproduced left andright-channel audio signals are supplied to audio output terminals OUT₁and OUT₂ through amplifiers 49 and 50.

On the other hand, in the subcode output by the EFM demodulating circuit42, two bits corresponding to channels P and Q are supplied to thesystem controller 32, and six bits corresponding to channels R through Ware supplied to a de-interleave and error correction circuit 52 in whichthe de-interleave of the six bits of the channels R through W and theerror correction using the parity Q and P are performed. Output data ofthe de-interleave and error correction circuit 52 is supplied to amode/instruction decoder 53. The mode/instruction decoder 53 isconfigured to decode the mode represented by the three bits of thechannels R through T of the symbol 0 of each pack, the mode designatedby the item represented by the three bits of the channels U through W ofthe symbol 0 of each pack, and the instruction represented by the sixbits of the channels R through W of the symbol 1 of each pack, and tosupply to each part signals respectively indicative of the modes and theinstruction. The output data of the de-interleave and error correctioncircuit 52 is supplied to a graphic code detection circuit 90. Thegraphic code detection circuit 90 is configured to generate a graphiccode detection signal when a code constituting a picture processinginstruction is outputted from the de-interleave and error correctioncircuit 52. The output of this graphic code detection circuit 90 issupplied to the system controller 32.

Furthermore, the output data of the de-interleave and error correctioncircuit 52 is supplied to a picture memory device 55. The picture memorydevice 55 includes sixteen RAMs 56a through 56p having addressesrespectively corresponding to all pixels on a picture having 50 "fonts"by 18 "fonts" in the row and column directions, and four bits of datacan be stored in each address, and a memory control circuit 57 forsensing data indicating the color number of each pixel of each picturechannels in the output data of the de-interleave and error correctioncircuit 52 according to the modes and the instruction indicated by theoutput of the mode/instruction decoder 53 and writing them in thecorresponding addresses of the RAMs 56a through 56p, and for reading outsequentially in a predetermined order one memory content of the RAMs 56athrough 56p corresponding to the picture channel designated by a data dby the key operation in an operation part 60 in accordance withhorizontal and vertical sync signals h and v.

The data output by the picture memory device 55 is supplied to a colorlook-up table 58 (this table being referred to hereinafter as the CLUT).The CLUT 58 is configured to detect the "load CLUT color 0 through color7" instruction and the "load CLUT color 8 through color 15" instructionfrom the output data of the de-interleave and error correction circuit52 in accordance with the modes and the instruction indicated by theoutput signal of the mode/instruction decoder 53, and hold the colordata corresponding to each color number, and configured to select andoutput color data of the color number designated by the data read-outfrom the picture memory 55.

The output data of this CLUT 58 is made up of three data typesrespectively representing the level of one of the R, G, B color signalsby using four bits. The three data types output by the CLUT 58 andindicating the levels of the R, G, B color signals are supplied to D/Aconverting circuit 61, 62, and 63, and converted to analog signals.Output signals of these D/A converting circuits 61 through 63 aresupplied to an analog-to-video converting circuit 65. Theanalog-to-video converting circuit 65 is configured, for example, toform a video signal of the NTSC system by the steps of obtaining aluminance signal and two color difference signals by the output signalsof the D/A converting circuits 61 through 63, generating a color carriersignal by adding signals obtained by the parallel modulation of twocolor subcarrier signals having a phase difference of 90° by means ofthe two color difference signals, and combining the color carrier signaland the luminance signal by the summation, and adding sync signalsthereto. By this analog-to-video converting circuit 65, the outputsignals o f the D/A converting circuits 61 through 63 are converted to avideo signal and sent subsequently.

In addition, the output of the de-interleave and the error correctioncircuit 52 is also supplied to a transparency control table 66 (thistable being referred to hereinafter as the TCT). The TCT 66 isconfigured to detect a "load TCT" instruction in the output data of thede-interleave and error correction circuit 52 in accordance with themodes and instruction indicated by the output signal of themode/instruction decoder 53, hold transparency control bits TCB-0through TCT-15, and output be selecting one of the TCB-0 through TCB-15being held, corresponding to a color number indicated by the dataread-out from the picture memory device 55.

The output signal of the TCT 66 is supplied to a video switch 33 as acontrol signal. In addition to the output signal of the TCT 66, thevideo format signal obtained from the subcode and output by theanalog-to-video converting circuit 65, and the video format signaloutput by the video format signal demodulating and processing circuit 30are supplied to the video switch 33.

In the video switch 33, the video format signal obtained from thesubcode is supplied to a stationary contact x of the changeover switch68, and also supplied to a stationary contact y through a resistor R₁.No connection is made to a stationary contact z of the changeover switch68. The changeover switch 68 is configured to selectively output one ofthe signals supplied to its stationary contacts x, y, z by moving itsmovable contact u to be in contact with one of the stationary contactsx, y, z in accordance with a control signal issued from the TCT 66. Thevideo format signal output from the video format signal demodulating andprocessing circuit 30 is directly supplied to a stationary contact z ofa changeover switch 69 and also supplied to its stationary contact ythrough a resistor R₂. No connection is made to a stationary contact xof the changeover switch 69. The changeover switch 69, like thechangeover switch 68, is configured to move its movable contact u to bein contact with one of its stationary contacts x, v, z in accordancewith the control signal. The movable contacts u, of each of thechangeover switches 68 and 69 are mutually connected. A resistor R₃ isconnected between a common junction J of the movable contacts u, u andground. A mixed signal of the video format signal obtained from thesubcode and the video format signal outputted from the video formatsignal demodulating and processing circuit 30 is derived at the commonjunction J. When the movable contacts u, u of the changeover switches 68and 69 are in contact with the stationary contacts x, x respectively,the mixing ratio of the video format signal obtained from the subcodebecomes 100%, and the mixing ratio is reduced to 0% when the movablecontacts u, u are in contact with the stationary contacts z, z. When, onthe other hand, the movable contacts z, z are in contact with thestationary contacts y, y, the mixing ratio is equal to M which isdetermined by the resistors R₁ and R₂, and the resistance of theresistors R₁ and R₂ are selected so that M has a value between 20% and80%. The signal derived at the common junction J is supplied to a videooutput terminal OUT₃.

A position detector 70 is provided in the vicinity of the path of themovement of pickup 22 along the radial direction of disc, and serves todetect when the beam spot emitted from the pickup 22 has reached aposition corresponding to the vicinity of the boundary between the CDare and the video area of a composite disc, to produce a detectionsignal. By the generation of this detection signal, a state that thepickup 22 has reached to the video area can be detected The positiondetector 70 can have a known structure including for example an opticalsensor. The detection signal outputted by the position detector 70 issupplied to the system controller 32.

The system controller 32 comprises a microcomputer which consists of aprocessor, a ROM (read only memory), a RAM and so on. The systemcontroller 32 is supplied with various signals and information such asthe horizontal sync signal h, the vertical sync signal v, and thecontrol data c, the P-channel and Q-channel bits in the subcodeoutputted from the EFM demodulation circuit 42, disc designationinformation from the control part 60 indicating whether the disc to beplayed is a compact disc or a composite disc, and mode designationinformation from the operation part 60, indicating whether thereproducing area is either the CD area or the video area, or both CD andvideo areas in the case of the playback of a composite disc. In thissystem controller 32, the processor executes processing of the signalsinput in accordance with programs previously stored in the ROM, andperforms the control operation of each part of the video format signaldemodulating and processing circuit 30, the selector switch 35, a drivecircuit (not shown) for driving the spindle motor 21, the drivingcircuit 71 for driving the slider motor, and the display part 72.

FIG. 12 is a block diagram showing a specific circuit construction ofthe video format signal demodulating and processing circuit 30. Asshown, the RF signal from the RF amplifier 26 is demodulated at ademodulation circuit 75, then supplied to a time base correction circuit76 and to a separator circuit 77. In the separator circuit 77, thehorizontal sync signal h, the vertical sync signal v and the controldata c which are contained in the video format signal are extracted. Thetime base correction circuit 76 consists of, for example, a variabledelay element of e.g. CCD (charge coupled device) and configured to varythe delay amount of that element in accordance with a control signalfrom a time base control circuit 78. The time base control circuit 78 isconfigured to output as the control signal a signal corresponding to aphase difference between an oscillation signal and its divided signal ofa crystal oscillator (VCO) 79 which oscillates, for example, insynchronism with the horizontal sync signal h extracted at the separatorcircuit 77, and the horizontal sync signal and the color burst signal ofthe video signal transmitted through the time base correction circuit76. For more specific configuration, reference is directed for exampleJapanese patent application laid-open number P56-102182.

The video signal having been processed by the time base correctionoperation is used as one input of a selector switch 80, and alsosupplied to an A/D converter 82 through an LPF (Low Pass Filter) 81. Inthe A/D converter 82, the sampling of the video signal is performed atintervals of a predetermined period, and the thus obtained sampledvalues are in turn converted to digital data. The output data of the A/Dconverter 82 is supplied to a video memory 83 consisting of a RAM(random access memory) and so on. A memory having a capacity for storingvideo information of at least one field long is used as the video memory83. Address and mode controls of this video memory 83 are performed by amemory control circuit 84. The memory control circuit 84 is configuredto perform control operations for sequentially read-out data written ineach address of the video memory 83 in accordance with a clock from areference clock generating circuit 85, and for rewriting the contents ofeach address of the video memory 83 in response to a write enable signalw which is outputted from the system controller 32. The data read-outfrom the video memory 83 is converted to an analog signal in a D/A(digital to analog) converter 86, and supplied through an LPF 87 as theother input to the selector switch 80. The selector switch 80 isnormally held at a position a to selectively output the video formatsignal directly supplied from the time base correction circuit 76, andswitched to a position b in response to a changeover command from thesystem controller 32, to selectively output the video format signalhaving been processed through the video memory 83.

Operations of the processor in the system controller 32 in the aboveconfiguration will be specifically explained with reference to theflowcharts of FIGS. 13 and 14.

Assume that a composite disc is set in a playback position. When a startcommand is issued in this state, the processor transmits a drive commandto the motor driving circuit 71, so that the slider motor 24 is drivento move the pickup 22 to an innermost peripheral position (step S1). Ifit is detected that the pickup 22 has reached the innermost peripheralposition by means of a detector switch of any usual configuration (notshown), the processor executes a focusing operation of the pickup 22,and performs the read-in of index code information which is recorded inan audio lead-in area at an innermost peripheral area of the disc (stepS2). Subsequently, the processor judges whether or not the disc beingset is a composite disc or not, on the basis of the read information(step S3). If it is judged that the disc being set is a compact disc,then the execution directly proceeds to a CD playback mode (step S4) anda playback operation is continuously performed unless any command forthe programmed music selecting operation for example has been issued.Since the playback operation in the CD playback mode itself is wellknown, the explanation thereof is omitted here.

If it is judged in step S3 that the disc being set is a composite disc,the processor immediately accelerates the slider motor 21 to a maximumrated speed of rotation for the video area (step S5). At the same time,the processor moves the pickup 22 toward the outer periphery of disc ata high speed by driving the slider motor 24 at a high speed (step S6).After these operations, when it is detected that the pickup 22 hasreached to the video area by the detection signal from the positiondetector 70 (step S7), the processor starts the playback operation ofthe video area (step S8). During video area playback, the processorperforms the control operation for writing the video information of atleast one field (or one frame) long obtained from the disc in the videomemory 83. This video information to be written may be, for example,first information in the video area, or designated by an addressdesignation through the key operation of the operation part 60.

If it is detected in step S9 that the playback of the video area hasbeen completed, then the processor decelerates the spindle motor 21 tothe maximum rated speed of rotation for the CD area (step S10). At thesame time, the processor drives the slider motor 24 at a high speed, tomove the pickup 22 to the innermost peripheral position of the disc at ahigh speed (step S11). If it is detected (step S12) that the pickup 22has reached the innermost peripheral position by the detection outputsignal of the above mentioned detector switch (not illustrated), theprocessor starts playback operation of the CD area (step S13).Concurrently to this, the selector switch 80 in the video format signaldemodulating and processing circuit 30 is changed over by the processorto the position b thereby selecting and outputting the video informationwhich was written in the video memory 83 during video area playback.Thus, playback of a still picture is performed during CD area playback.When the completion of the CD area playback is detected by reading theinformation of audio lead-out (step S14), the processor initiate thedriving of the slider motor 24 to move the pickup 22 to its homeposition (step S15) unless any operational command is present.Furthermore, a loading mechanism (not shown in the drawings) performsdisc ejection (step S16), to complete the playback operating sequence.

During the execution of the main routine, the processor proceeds to stepS20, by an interruption by means of a timer for example, to judgewhether or not a chapter search operation is commanded by a keyoperation in the operation part 60. If it is judged in step S20 that thechapter search operation is commanded, the processor moves theinformation detection point of the pickup 22 to a start point of thedesignated chapter, by transmitting the drive command to the motordriving circuit 71 while comparing the chapter number of the designatedchapter and the chapter number data in the control data c outputted fromthe separator circuit 77 in the video format signal demodulating andprocessing circuit 30 (steps S21 and S22), and calls the routine afterstep S8, and executes it subsequently (step S23).

If it is judged in step S20 that the chapter search operation is notcommanded, the processor fetches the chapter number data in the controldata c (step S24). Then, the processor judges whether or not the presentvalue of the chapter number obtained in step 23 is equal to the previousvalue of the chapter number stored in a predetermined address of the RAMin the system controller (step S25).

If it is judged in step S21 that the present and previous values of thechapter number are equal to each other, the processor immediatelyrestarts the execution of the routine which was being executedimmediately before the shift to the step S20. On the other hand, if itis judged in step S25 that the present and previous values of thechapter number are not equal to each other, the processor writes thepresent value of the chapter number in the predetermined address of theRAM in the system controller 32 as the previous value of the chapternumber (step S26), and judges whether or not the graphic code detectionsignal is being output from the graphic code detection circuit 90 (stepS27).

If it is judged in step S27 that the graphic code detection signal isbeing output, the processor transmits to the display part 72 a commandfor displaying the presence of picture information by the subcode (stepS28), and restarts the execution of the routine which was being executedimmediately before the shift to the step S20.

If it is judged in step S27 that the graphic code detection signal isnot being output, the processor transmits to the display part 72 acommand for displaying the absence of picture information by the subcode(step S29), and restarts the execution of the routine which was beingexecuted immediately before the shift to the step S20.

In the operating sequence described above, playback of the informationrecorded in the CD area of the composite disc is performed in steps S10through S14 after the playback of information recorded in the video areain steps S1 through S9.

When the "load CLUT color 0 through color 7" instructions and the "loadCLUT color 8 through color 15" instructions are decoded by themode/instruction decoder 53 during video area playback, data ofdesignated 16 colors among 4096 colors are held in the CLUT 58.

Subsequently, by decoding the "write font foreground/background"instruction etc., picture data of 16 channels are in turn stored in theRAM 56a through 56p in the picture memory device 55. When one of thepicture data of 16 channels is designated by data corresponding to thekey operation in the operation part 60, picture data of the designatedchannel is sequentially output from the picture memory device 55, and inturn supplied to the CLUT 58. By this operation, color data of a colornumber indicated by the picture data is then output from the CLUT 58. Avideo format signal based on this color data is outputted from theanalog video converting circuit 65, and supplied to the video switch 33.

If the "load TCT" instruction is decoded in this state, the transparencycontrol bits TCB-0 through TCB-15 respectively corresponding to eachcolor number are then held in the TCT 66. Among the TCB-0 through TCB-15being held, one corresponding to the color number indicated by the dataread-out from the picture memory device 55 is selectively outputted fromthe TCT 66, and the mixing ratio in the video switch 33 is designated bythe output of the TCT 66. Thus, the mixing ratio between the videoformat signal outputted from the analog-to-video converting circuit 65and the video format signal outputted from the video format signaldemodulating and processing circuit 30 is controlled for each pixel.Consequently, a combination of pictures such as illustrated in FIG. 15is made possible. Specifically, the mixing ratio is set to 100% for aportion corresponding to each pixel outside a region D of a picture Abased on the video format signal output from the video format signaldemodulating and processing circuit 30, and set to 0% for a portioncorresponding to each pixel within the region D. On the other hand, themixing ratio is set to 0% for a portion corresponding to each pixeloutside a region D, of a picture B based on the video format signaloutputted from the analog-to-video converting circuit 65, and set to100% for a portion corresponding to each pixel within the region D' ofthe picture B. Then a picture C can be formed by combining the portionof the picture A outside the region D and and the portion of the pictureB within the region D'.

In this way, it is possible to compose a picture as illustrated in FIGS.16A through 16C, in which a translation of a dialogue, a musical score,or an explanation of a scene, etc., obtained from the subcode isinserted into a moving picture obtained by the video format signalrecorded in the video area or a still picture obtained by the videomemory 83.

Moreover, when the chapter search operation is commanded, the designatedchapter is searched through operations of the steps S20 through S23, andthe playback operation starts from the chapter searched out. Since thegraphic codes are recorded as a subcode correspondingly to the chapters,incomplete reading of a series of graphic codes is prevented, so thatthe picture corresponding to the subcode is displayed precisely.

Moreover, since the presence or absence of the picture corresponding tothe subcode is displayed through the operations of the steps S24 throughS29, it can be readily recognized that the system is operating properlyeven if the picture by the subcode is not displayed during the playbackof a chapter in which picture information is not recorded as thesubcode.

As explained in detail in the foregoing, the system of recording andreproducing picture information according to the present invention isconfigured such that, in addition to a video format signal and a codedinformation signal, graphic codes including picture information arerecorded on a recording medium correspondingly to playback sections ofthe video format signal, the graphic codes being inserted as the subcodeof the coded information signal, and at the time of playback of therecording medium, a picture signal according to graphic codescorresponding to the playback section is produced. By this feature, itis possible to prevent an incomplete reading of a series of graphiccodes when a desired playback section is searched for the playback.Thus, the picture by the subcode can be displayed precisely.

Furthermore, during playback of the recording medium, through thedisplay of the presence and absence of the graphic codes, it can bereadily recognized that the system is operating properly even if thepicture corresponding to the subcode is not displayed during theplayback of a playback section in which no picture information isrecorded as the subcode.

What is claimed is:
 1. A method of recording and reproducing pictureinformation on a recording medium comprising the steps of:extracting aninformation signal representing playback sections from a video formatsignal to be recorded on a recording medium; generating graphic codesincluding picture information; recording said video format signal and acoded information signal on a recording medium coordinated with theplayback sections of said video format signal in accordance with saidinformation signal extracted from said video format signal, said graphiccodes being inserted as the subcode of said coded information signal;and playing back the video format signal from said recording medium andsimultaneously generating a signal according to said graphic codescorresponding to the playback section of said video format signal eachtime one playback section of said video format signal is played back. 2.A method as set forth in claim 1, further comprising a step fordisplaying, at the time of playback of said recording medium, presenceor absence of said graphic codes each time of the playback of oneplayback section of said video format signal.
 3. An apparatus forplaying a picture information recording medium on which a video formatsignal and a coded information signal together with graphic codesincluding picture information are recorded, said graphic codes beinginserted as the subcode of said coded information signal, said apparatuscomprising:pickup means for reading signals recorded on said recordingmedium and generating a pickup output signal; video format signaldemodulating means for demodulating said video format signal from saidpickup output signal; means for driving said pickup means to read aparticular playback section of said video format signal in response to auser's operation command; coded information signal demodulating meansfor demodulating said coded information signal from said pickup outputsignal; graphic code demodulating means for demodulating said graphiccodes from an output signal of said coded information signaldemodulating means; and picture signal generating means for generating apicture signal according to said graphic codes from an output signal ofsaid graphic codes demodulating means each time one playback section ofsaid video format signal is played back.
 4. An apparatus as set forth inclaim 3, further comprising display means for displaying, at the time ofplayback of said recording medium, presence or absence of said graphiccodes each time one playback section of said video format signal isplayed back.
 5. A method of recording and reproducing audio and videoinformation to and from a recording medium comprising the stepsof:generating a video format signal to be recorded on the disk includingchapter numbers inserted therein to identify playback sections of thevideo format signal, a chapter number code being assigned to eachplayback section of the video format signal; generating graphic codesrepresentative of picture information and instruction code informationfor superimposing the picture information on the video format signal,said graphic codes including mixing ratios for mixing the pictureinformation of the graphic codes with the video format signal;extracting the chapter numbers from the video format signal; matchingeach chapter number with a corresponding graphic code for superimposingthe picture information on a corresponding playback section of the videoformat signal; generating an audio signal to be recorded on the disk;digitizing the audio signal to generate a digital audio signal;inserting the graphic codes as a subcode to the digital audio signal toform a coded information signal; frequency modulating the video formatsignal to generate a frequency modulated video format signal;superimposing the coded information signal on the frequency modulatedvideo format signal; recording the coded information signal and thefrequency modulated video format signal with the superimposed codedinformation signal on the disk; and playing back the information fromthe disk comprising and simultaneously generating the pictureinformation according to said graphic codes corresponding to the chapterof the video format signal specified by the chapter search number eachtime the corresponding playback section of the video format signal isplayed back.
 6. The method of claim 5, and further comprising the stepof displaying the presence or absence of said graphic codes duringplayback of said motion picture signal.
 7. The method of claim 5, andfurther comprising the steps of:issuing a chapter search commandincluding a chapter search number upon a user desiring playback of aparticular chapter of the video format signal; and playing back thevideo format signal from the playback section of the disk correspondingto the chapter search number.